Persistent halogenated compounds in aquaculture environments of South China: Implications for global consumers’ health risk via fish consumption

This study examined the potential sources of persistent halogenated compounds (PHCs), including organochlorine pesticides, mainly DDXs (sum of o,p′- and p,p′-DDT, -DDD, and -DDE and p,p′-DDMU) and polybrominated diphenyl ethers, to typical aquaculture environments of South China, determined the relative importance of gill diffusion and fish feeding for exposure of fish to these contaminants and assessed potential health risk for global consumers via consumption of fish from South China. Fish feed is generally a direct and important source of PHCs in both freshwater and seawater aquaculture. In addition, gill diffusion is the predominant uptake route for PHCs (except p,p′-DDMU, o,p′-DDD and -DDT) in farmed freshwater fish, whereas accumulation from the diet is the major route for farmed marine fish. Risks to health of global consumers via consumption of fish from South China are minimal. However, increased risk can be foreseen due to continuous use of brominated fire retardants and electronic waste importation to China.

► Feeding is the main input route for DDTs and polybrominated diphenyl ethers (PBDEs) to mariculture zones in South China.
► Feeding and atmospheric deposition are the main routes for DDTs and PBDEs, respectively, to freshwater farming zones.
► Consumption of fish cultured in South China poses minimal health risk to global consumers.
► Use of compound feed produced under controlled conditions should be encouraged in fish farming.